Gas injection apparatus with heating channels

ABSTRACT

A gas injection apparatus for a thermal processing chamber includes a gas injector having an inlet at a first end and a port at a second end; and a plate having a first opening matching the port, one or more second openings, and at least one circuitous flow path defined by the plate and fluidly connecting the first opening to the one or more second openings.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.15/859,035, filed Dec. 29, 2017, which claims benefit of U.S.Provisional Patent Application Ser. No. 62/441,710, filed Jan. 3, 2017,which is incorporated herein by reference.

BACKGROUND Field of the Invention

Embodiments of the present invention generally relate to methods andapparatus for processing semiconductor substrates. More specifically,embodiments of the present invention generally relate to methods andapparatus for oxygen for deposition on semiconductor substrates.

Description of the Related Art

Thermal CVD chambers are widely used in semiconductor manufacturing, andin other industries, to form film layers on substrates. Generally, thesubstrate is heated, for example using lamp electromagnetic radiationthat heats the substrate, and the hot substrate is exposed to a gasmixture to perform a chemical reaction that forms a thin film on thesubstrate. Reactions occur in the gas space above the substrate andbetween species in the gas space and the substrate surface to form thethin film on the substrate. An exemplary process is the reaction ofhydrogen gas and oxygen gas to form an oxide layer on the surface of asemiconductor substrate. Hydrogen gas and oxygen gas activate,decompose, and react together to form various active species in the gasspace, and reactive species in the gas space react with semiconductormaterials such as silicon and germanium on or within the substratesurface to form oxides of silicon and/or germanium. In the typicalprocess, the reaction among the components in the gas mixture, and withthe substrate surface, is primarily activated by the heat of thesubstrate, which may be conducted and radiated to the gas in variousproportions depending on operating pressure and gas flow characteristicsof the chamber. The gas can also absorb some heat directly from the lampelectromagnetic radiation.

In one category of thermal CVD chambers, the gas mixture is introducedthereinto through a side wall of the chamber near an edge of thesubstrate. The gas enters the chamber on one side and flows across thesubstrate to an exhaust on the opposite side of the chamber, absorbingheat from the substrate, and the surrounding chamber environment, and itresultantly rises in temperature. The substrate may be rotated while thegas is introduced into the chamber and is passing across the substrate.When a gas molecule reaches an activation temperature, it becomesactivated, for example by ionizing, decomposing, or merely reaching anactive quantum state. As the gas generally rises in temperature, somemolecules in the gas become reactive enough for CVD reaction to begin,and the rate of reaction generally rises. If the reaction emits visiblelight, as the reaction rate rises, a reaction front can be viewed at thelocation(s) where a high enough concentration of gas molecules areactivated, such that enough photons are emitted to be seen. Visibilityof the reaction front thus indicates that a certain relatively highreaction rate has been achieved.

Commonly, the reaction front is located some distance from the edge ofthe substrate because it takes time for the gas temperature to rise tothe activation temperature while flowing across the substrate. Distancebetween the substrate edge and the reaction front indicates that thesubstrate-gas reaction or the thin film formation rate is slow near theedge of the substrate where the gas is mostly too cool to react. Becausethe reaction proceeds faster nearer the center of the substrate than theedge due to the time required for the gas to rise to the activationtemperature, as evidenced by the location of the reaction front, theresulting film formed on the substrate, or the surface modificationthereof, is substantially non-uniform in thickness.

Non-uniformity in the surface modification or the thickness of the thinfilm formed in thermal CVD processes is increasingly disadvantageous inadvanced manufacturing processes due to the variation in deviceproperties arising from these variations. Therefore, what is needed isan apparatus and method for improving uniformity of thin film depositionthickness and surface modification in thermal CVD processes.

SUMMARY

In an embodiment, a gas injection apparatus for a processing chamberincludes a gas injector having an inlet at a first end, a closed secondend, and an extending conduit located between the first end and thesecond end; and a transparent manifold plate gas heater having an inletthat matches and fluidly couples to the extending conduit, one or moreoutlets, and one or more channels formed in the manifold plate gasheater and fluidly connecting the inlet of the manifold plate gas heaterto the one or more outlets.

In another embodiment, a processing chamber includes a gas injectionapparatus comprising a gas injector having an inlet at a first end, aclosed second end, and an extending conduit located between the firstend and the second end; and a transparent gas heating plate having afirst major surface and a second major surface opposite the first majorsurface, a first opening that matches and fluidly couples to theextending conduit and a second opening, the transparent gas heatingplate defining at least one circuitous gas flow path from the firstopening to the second opening; and a radiant heat source facing thetransparent gas heating plate.

In another embodiment, a processing chamber includes a chamber bodyhaving a side wall with a first gas inlet, a second gas inlet, and anexhaust opposite the second gas inlet; a substrate support disposed inthe chamber body and defining a substrate processing plane proximate tothe first and second gas inlets and the exhaust; a heat source facingthe substrate support; a divider between the heat source and thesubstrate support; and a resistive gas heater coupled to the first gasinlet.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentdisclosure can be understood in detail, a more particular description ofthe disclosure, briefly summarized above, may be had by reference toembodiments, some of which are illustrated in the appended drawings. Itis to be noted, however, that the appended drawings illustrate onlyexemplary embodiments and are therefore not to be considered limiting ofits scope, and may admit to other equally effective embodiments.

FIG. 1A is cross-sectional view of one embodiment of a thermalprocessing chamber.

FIG. 1B is a detailed view of a portion of the thermal processingchamber of FIG. 1A.

FIG. 1C is a detailed view of another embodiment of a manifold usable inthe thermal processing chamber of FIG. 1A.

FIGS. 2A-2F are bottom views of manifold embodiments for thermalprocessing chambers.

FIG. 3A is an exploded perspective view of a manifold, gas injector, andmanifold support, according to one embodiment.

FIG. 3B is an isometric view of a gas injector according to oneembodiment.

FIG. 3C is an exploded perspective view of a manifold, gas injector, andmanifold support, according to another embodiment.

FIG. 3D is an isometric view of a gas injector according to anotherembodiment.

FIG. 4A is a perspective cross-sectional view of another thermalprocessing chamber.

FIG. 4B is a top view of a blocker plate usable in the thermalprocessing chamber of FIG. 4A.

FIG. 4C is a detailed view of the blocker plate of FIG. 4B.

FIG. 5 is a schematic top view of another thermal processing chamber.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements and features of oneembodiment may be beneficially incorporated in other embodiments withoutfurther recitation.

DETAILED DESCRIPTION

In a thermal CVD chamber having a radiant heat source that is used toheat a substrate during processing, a gas injection apparatus isutilized to provide reaction precursors, in a gas state, into aprocessing volume of the chamber. Here, the gas injection apparatusfeeds one or more of the reaction precursors to an injection manifoldthat is heated by the heat source, to resultantly heat the one or moreof the gaseous reaction precursors before they are injected into theprocessing volume of the chamber. The injection manifold is a gasheating plate, and includes channels that fluidly couple the gasinjection apparatus to the processing volume of the chamber, so that oneor more reaction precursors flow from the gas injection apparatusthrough the channels of the injection manifold and thence into theprocessing volume of the chamber. As the reaction precursors flowthrough the injection manifold, the reaction precursors absorb heat fromthe injection manifold, which is heated by the chamber heat source, herethe radiant heat source. The channels provide an extended flow length toextend the time the gas is passing over a heated surface, therebyallowing the reaction precursors to rise in temperature before they areexposed to the substrate. The channels, in conjunction with outletstherefrom into the processing volume of the chamber, also provide thecapability to direct the hot reaction precursors to desired locations ofthe substrate surface to promote uniform film layer deposition, orsurface modification, on the exposed surface of the substrate. Thechannels are generally pathways through the injection manifold thatprovide enough residence time for the reaction precursors to achieve anelevated temperature while passing therethrough that is near, at, orabove an activation temperature of the reaction precursors. Thus, thechannels can be circuitous pathways through the injection manifold.

One example of a thermal CVD chamber that can benefit from such gasinjection apparatus is a thermal semiconductor oxidation chamber. FIG.1A is cross-sectional view of one embodiment of a thermal processingchamber 100 that can be used to perform a thermal oxidation process on asemiconductor substrate or on one or more film layers previously formedthereon. Aspects of the chamber 100 of FIG. 1A are similar to theRADIANCE®, RADIANCE® Plus, and RADOX® chambers available from AppliedMaterials, Inc., located in Santa Clara, Calif.

The processing chamber 100 includes a chamber body 102, and a substratesupport 140 disposed within the chamber body 102. A radiant heat source160 provides heat to activate the reactions of the reaction precursorswith the substrate surface, and a divider 165 separates the heat source160 from the processing environment. The radiant heat source 160 heatscomponents and surfaces of the chamber 100 that receive electromagneticradiation from the radiant heat source 160, and the heated componentsand surfaces, in turn, heat the reaction precursors. During processing,a substrate 104 is supported in a processing position by the substratesupport 140. The substrate 104 and the divider 165 define a processingvolume 120 within which the substrate 104 is exposed to reactionprecursors. The heat source 160 emits visible and infrared radiationthat heats chamber components and the substrate 104. In this case, theheat source 160 is a lamp assembly with a plurality of lamps that emitvisible and infrared electromagnetic radiation which is absorbed by, andthereby heats, the substrate 104, along with the divider 165 and othersurface and components of the chamber 100. Alternatively, solid stateemitters, such as LEDs and lasers, can be used to emit electromagneticradiation to heat the substrate 104. The divider 165 is substantiallytransparent to the electromagnetic radiation emitted by the heat source160, but absorbs enough to be heated. Electromagnetic radiation thatpasses through the divider 165 reaches the substrate 104, heating thesubstrate 104. The divider 165 can be quartz or sapphire.

The substrate support 140 in FIG. 1A is a substrate edge support. Acontact portion 125 of the substrate support 140 contacts the edge ofthe substrate 104, suspending the substrate 104 between a base 139 ofthe chamber 100 and the divider 165. A support portion 121 of thesubstrate support 140 extends away from the contact portion toward thebase 139 and rests on a rotor 123, which can be rotated and therebyrotate the substrate 104 about its center on the diameter thereof duringprocessing. The rotor 123 of FIG. 1A is a magnetically actuated rotor,with a non-magnetic envelope 127 thereof enclosing a magnetic core 129therein, which magnetic core 129 is a permanent magnet. Anelectromagnetic stator 131 is disposed outside the chamber body 102 inregistration with, and surrounding, the rotor 123. Electromagnets (notshown) in the stator 131 are operated to provide a rotating magneticfield that rotates the rotor 123 by magnetic coupling of the rotatingmagnetic field of the stator 131 with the magnetic core 129. A linearactuator 133 can be used to change the position of the stator 131 alonga rotational axis of the rotor 123 such that the rotor 123 can be movedalong its axis of rotation while it is rotating, or while it is notrotating. In this case, the linear actuator 133 is a lead screw drivewith a lead screw coupled to a rotator and a threaded sleeve, which inturn is coupled by a support to the stator 131. In this way, theposition of the substrate 104 in the chamber body 102 can be changed.

The substrate 104 is disposed in the chamber 100 and removed from thechamber 100 using lift pins 143. Although one lift pin 143 is visible inFIG. 1A, the chamber 100 has three lift pins 143. An opening 141 in thechamber base 139 provides access for the lift pin 143 to contact thesubstrate 104 and to retract into the chamber base 139 duringprocessing. The lift pins 143 of the chamber 100 are disposed in anenvelope 149 attached to the chamber base 139 at the opening 141. Theenvelope 149 encloses the opening 141 to maintain a seal around theopening 141. One or more compliant seal members (not shown) may beprovided where the envelope 149 attaches to the chamber base 139. One ormore actuators 147 are provided in the envelope 149. The actuators 147in FIG. 1A are electromagnets, configured to provide magneticallycoupled actuation for the lift pin 143. A power supply (not shown) forthe electromagnets may be located along the chamber base 139 to accessthe lift pins 143. The power supply may be insulated against chamberheat if necessary. The lift pins 143 are extended toward the processingvolume 120 for substrate loading and unloading. The lift pins 143 mayextend into the processing volume 120, or the substrate support 140 mayconcurrently be lowered while the lift pins 143 are extended, in whichcase the lift pins 143 might not extend into the processing volume 120.The lift pins 143 move into contact with the substrate 104, and bymotion of the lift pins 143 alone, or together with motion of thesubstrate support 140 by actuating the stator 131, the substrate 104 isseparated from the substrate support 140 to provide access for asubstrate handler (not shown) to receive the substrate 104 from the liftpins 143 and support the substrate 104 thereon for removal from thechamber body 102. The substrate handler removes the substrate from thechamber body 102 through a resealable door provided in the portion ofthe chamber body 102 removed by the cross-section of FIG. 1A. Substratesare also loaded into the chamber body 102 through the door. Thesubstrate handler, having a substrate supported thereon, extends intothe chamber 100 above the substrate support 140. The lift pins 143extend to lift the substrate 104 off the substrate handler, which thenexits the chamber 100. The lift pins 143 then retract to place thesubstrate on the substrate support 140. The substrate support 140 mayalso be moved to contact the substrate 104 and lift the substrate 104off the lift pins 143. The lift pins 143 are then retracted toward thechamber base 139 and the substrate support is moved into processingposition.

Delivery of reaction precursors to the chamber 100 is accomplished usingtwo openings in the side wall of the chamber body 102. A first opening169 is provided at a first location in the side wall for injecting afirst gas, and a second opening 126 is provided at a second location inthe side wall, different from the first location, for injecting a secondgas. The first and second gases react together when an activationtemperature is reached, so the first and second gases are injected atseparate locations, and flow along different pathways to avoid unwantedpremature reactions therebetween, and to allow one of the gas pathwaysto be heated, as further described below. In FIG. 1A, the first opening169 and the second opening 126 are separated from each other by an angleof about 90° in the rotational direction of the substrate support 140.

The processing chamber 100 includes a manifold gas heating plate 150that is disposed substantially parallel to a substrate processing planedefined by the substrate support 140, and a gas injector 170 that isdisposed in the opening 169 and fluidly coupled to the manifold gasheating plate 150. The manifold gas heating plate 150 is located betweenthe divider 165 and the substrate support 140. The manifold gas heatingplate 150 is flat and disk-shaped, for example a plate with a firstmajor surface 166 and a second major surface 167 opposite the firstmajor surface 167, and has a diameter larger than the outer diameter ofthe substrate support 140. The manifold gas heating plate 150 is madefrom a material such as quartz or sapphire that allows radiation fromthe heat source 160 to pass through the manifold gas heating plate 150to heat the substrate. The manifold gas heating plate 150 is thussubstantially transparent. The manifold gas heating plate 150 alsoabsorbs some electromagnetic radiation from the heat source 160, so themanifold gas heating plate 150 is also heated by the heat source 160.

The manifold gas heating plate 150 is located between the divider 165and the substrate support 140, and the divider 165 is located betweenthe manifold gas heating plate 150 and the heat source 160. The heatsource 160 emits electromagnetic radiation toward the divider 165. Thedivider 165 allows electromagnetic radiation to pass through and reachthe manifold gas heating plate 150. Some of the electromagneticradiation emitted by the heat source is absorbed by the divider 165 andheats the divider 165, while some passes through the divider 165 to heatthe substrate 104. To maintain a desired temperature of the divider 165,cooling may be provided to cool the divider 165, for example bycirculating a cooling fluid through channels formed in the divider.Alternatively, a cooling fluid may be applied to the divider 165 on asurface thereof facing the heat source 160 or facing the manifold gasheating plate 150. Electromagnetic radiation that passes through thedivider 165 reaches the manifold gas heating plate 150. Some of theelectromagnetic radiation that reaches the manifold gas heating plate150 is absorbed by the manifold gas heating plate 150 and heats themanifold gas heating plate 150, while some passes through the manifoldgas heating plate 150. Electromagnetic radiation that passes through themanifold gas heating plate 150 reaches the substrate 104 and heats thesubstrate 104.

The manifold gas heating plate 150 rests on the gas injector 170 and ona manifold support 196 disposed in a recess of the chamber side wallopposite the opening 169 The gas injector 170, manifold support 196, andmanifold gas heating plate 150 may be made of the same material, forexample quartz. Alternatively, other suitable materials may be used. Forexample, the manifold gas heating plate 150 may be made of quartz whilethe gas injector 170 is made of sapphire, or vice versa. The manifoldsupport 196 may be made of any process resistant material and does notneed to be transparent.

An inlet 180 formed in a surface of the manifold gas heating plate 150facing the substrate support 140 fluidly communicates with an extendingconduit 185 formed in the gas injector 170 to form a gas passage fromthe gas injector 170 into the manifold gas heating plate 150. One ormore outlets 190 are also formed in the surface of the manifold gasheating plate 150 facing the substrate support 140, which here is thesecond major surface 167, to allow reaction precursors to flow from themanifold gas heating plate 150 into the processing volume 120. One ormore channels are formed inside the manifold gas heating plate 150,between a first portion of the manifold gas heating plate 150 and asecond portion, as described further below, providing a fluid passagefrom the inlet 180 to the outlets 190. As the reaction precursor flowsthrough the channels, the heated manifold gas heating plate 150 heatsthe reaction precursor to an elevated temperature to promote reaction ofthe reaction precursors with the exposed surface of the substrate 104when the reaction precursor exits the manifold gas heating plate 150through the outlets 190. The extending conduit 185 may be sealed with aninner wall of the inlet 180 using a thermally resistant seal memberdisposed in the inlet 180 so that most or all reaction precursor(s)flowing through the gas injector 170 flow into the manifold gas heatingplate 150.

One of the outlets 190 is shown in detail in FIG. 1B. The outlet 190 isan opening in a side of the manifold gas heating plate 150 that facesthe substrate support 140 when installed in the chamber 100. The outlet190 does not extend through the thickness of the manifold gas heatingplate 150 from the first major surface 166 to the second major surface167, but joins with a channel 195 formed between a first portion 176 ofthe manifold gas heating plate 150 and a second portion 177 of themanifold gas heating plate 150. The manifold gas heating plate 150 isformed by joining the first portion 176 and the second portion 177. Thefirst portion 176 starts as a flat plate. The channels 195 are milled oretched into one side of the flat plate, and the outlets 190 and inlet180 are formed in the other side of the flat plate, which becomes thesecond major surface 167 of the manifold gas heating plate 150 uponassembly of the manifold gas heating plate 150. The outlets 190 andinlet 180 intersect with the channels 195. The second portion 177 isthen disposed on the first portion 176 covering the channels 195 and thetwo portions are joined, for example by welding, to form the manifoldgas heating plate 150. Channels may also be formed in the second portion177, optionally matching the channels of the first portion.Alternatively, the channels formed in the second portion 177 may have adifferent pattern from the channels formed in the first portion 176 toallow additional flow pathways through the manifold gas heating plate150.

FIG. 1C shows a detailed view of a manifold 151, like the manifold gasheating plate 150, with an outlet 191 that is angled to direct gas flowin a desired direction. Like the outlet 190, the outlet 191 does notextend through the manifold 151 from the first major surface 166 to thesecond major surface 167 thereof, and connects with a channel 195 formedbetween the first major surface 166 and the second major surface 167 ofthe manifold 151. The outlet 191 has an axis 192 that is notperpendicular to either the first major surface 166 or the second majorsurface 167.

The manifold gas heating plate 150 and/or the divider 165 may be coated.The coatings may include optical coatings and/or passivation coatings.Optical coatings may be used to control transmissivity and reflectivityof the coated member. For example, a spectral notch filter coating maybe used to reflect or absorb a specific wavelength or spectrum ofelectromagnetic radiation. Multiple such materials may be used in somecases to reflect or absorb selected wavelengths. Examples of suchcoatings include spectral notch filters. Anti-reflective materials canalso be included in a coating, for example as an anti-reflective layer.The coatings may be applied to either or both major surfaces 166, 167 ofthe manifold gas heating plate 150 and/or the divider 165. On themanifold gas heating plate 150 and/or the divider 165, ananti-reflective coating may be applied to the first major surface 166and a spectral notch filter coating may be applied to the second majorsurface 167.

In operation, a gas source is fluidly coupled to the gas injector 170.Reaction precursors are flowed into the gas injector 170, through theextending conduit 185 and inlet 180, into the manifold gas heating plate150, through the manifold gas heating plate 150 and to the outlets 190.While travelling through the manifold gas heating plate 150, thereaction precursors are heated by the manifold gas heating plate 150 toa temperature near, at, or above an activation temperature. When thereaction precursors exit the manifold gas heating plate 150 into theprocessing volume 120, the reaction precursors are reactive at alllocations along the substrate 104. A second reaction precursor isprovided through the second opening 126. The second reaction precursormay be heated to some extent, or may be provided at ambient temperature.By virtue of the preheating of the reaction precursor in the manifold,the first gas is at its activation temperature when it exits themanifold, and thus is able to immediately react with the second gas at alocation adjacent to the substrate to form the a film, or modify theexposed surface, on the substrate. In one embodiment, the first gas ishydrogen and the second gas is oxygen. The hot, active hydrogen reactsin the processing volume 120 with the oxygen to form reactive speciesthat react with the surface of a semiconductor substrate in theprocessing chamber 100. The reactive species include oxygen radicals andhydroxyl radicals that have increased reactivity to react with siliconand/or germanium in the substrate surface. Some hydrogen radicals arealso added to the substrate surface, either within the substrate belowthe surface or become attached to the surface Gas is exhausted from theprocessing chamber 100 through a port (not shown) located in the sidewall of the portion of the chamber 100 removed by the cross-section ofFIG. 1A. The exhaust is typically located approximately opposite thesecond opening 126, and may be located inside a passage formed in theside wall, and through which substrates are loaded and unloaded.

FIGS. 2A-2F show various embodiments of manifolds 150A-150F, viewing thesecond major surface 167 of each. Each embodiment includes at least oneinlet 180, several outlets 190, and channels 195-a through 195-f. Thechannels 195-a through 195-f are inside the manifolds 150A-F, betweenthe first major surface 166 (not shown) and the second major surface167, so the channels 195-a through 195-f are depicted in phantom. Eachembodiment of the manifold gas heating plate 150 has a first side thatis flat, and faces the divider 165 when the manifold gas heating plate150 and divider 165 are installed in the chamber 100, and a second sidewith one or more inlets 180 and one or more outlets 190. The manifoldgas heating plate 150A has a single inlet 180 fluidly coupled to aspiral channel 195-a inside the manifold gas heating plate 150A. Thespiral channel 195-a has a constant convergence (the spacing betweenneighboring passes of the spiral channel 195-a through a given radius ofthe manifold gas heating plate 150A is constant), and multiple outlets190 intersect the spiral channel 195-a at various points along thespiral channel 195-a. The spiral channel 195-a thus has the shape of anArchimedes spiral. The outlets 190 in FIG. 2A are arranged in a line,for example a straight line, along a radius of the manifold gas heatingplate 150A, on the side of the manifold gas heating plate 150A oppositethe inlet. Each pass of the spiral channel 195-a across a diameter ofthe manifold gas heating plate 150A drawn through the inlet 180intersects with an outlet 190 along the diameter on an opposite side ofthe center from the inlet 180. In this case, the spiral channel 195-aends at an outlet 190 near the center of the manifold gas heating plate150A.

The manifold gas heating plate 150B of FIG. 2B has two inlets 180located along a diameter of the manifold gas heating plate 150B atopposite edges of the manifold gas heating plate 150B. Each inlet 180 isfluidly coupled to a spiral channel 195-b. The manifold gas heatingplate 150B has two inter-circling spiral channels 195-b, each having thesame constant convergence to avoid the two spiral channels intersecting.A plurality of outlets 190 extend through the second major surface 167of the manifold gas heating plate 150B, in this case arranged along adiameter of the manifold gas heating plate 150B, and they intersect withthe spiral channels 195-b located within the manifold gas heating plate150B. A first plurality of outlets 190 are fluidly coupled to a firstspiral channel 195-b and a second plurality of outlets 190 are fluidlycoupled to a second spiral channel 195-b. On each side of the center ofthe manifold gas heating plate 150B, along the diameter of the manifoldgas heating plate 150B, is an inlet 180 near the edge of the manifoldgas heating plate 150B and a plurality of outlets 190. The outlets 190are arranged between the inlets 180 and outlets 190 on one side of thecenter of the manifold gas heating plate 150B are all connected to thesame spiral channel 195-b. The number of outlets 190 on each side of thecenter of the manifold gas heating plate 150B is different in this case,but the number may be the same.

A manifold with two inlets 180, like the manifold gas heating plate 150Bof FIG. 2B, may be used in the chamber 100 of FIG. 1A by providing asecond opening like the opening 169 in the side wall of the chamber body102 where the recess that accommodates the manifold support 196 isshown, and by providing a second gas injector like the gas injector 170in the second opening. The second gas injector would have a port likethe extending conduit 185 for engaging with the second inlet 180 of themanifold. A gas source would be connected to each gas injector 170, andreaction precursors would flow into the manifold gas heating plate 150Bfrom two opposite sides of the chamber 100. Such a manifold would allowflowing two different reaction precursors through the manifold gasheating plate 150B for heating via separate pathways prior to injectinginto the processing volume 120. Where multiple channels are formed inthe manifold, the channels may have the same length or different length.

FIG. 2C shows a manifold gas heating plate 150C like the manifold gasheating plate 150B, but with outlets 190 not all arranged along adiameter of the manifold gas heating plate 150C. The manifold gasheating plate 150C is also different from the manifold gas heating plate150B in that only one channel 195-c is provided, here with two inlets180 at opposite edges along a diameter of the manifold gas heating plate150C, as with the manifold gas heating plate 150B. The channel 195-c isa double-spiral channel forming a path that converges from the inlets180 toward the center of the manifold gas heating plate 150B at aconstant convergence. The outlets 190 are defined at symmetricallocations with respect to a diameter intersecting the inlets 180, withthe same number of outlets 190 for each converging segment of the spiralchannel 195-c.

FIG. 2D shows a manifold gas heating plate 150D with an irregularchannel 195-d formed in a back-and-forth pattern through the manifoldgas heating plate 150D. One inlet 180 is provided, and multiple outlets190 are provided on an opposite side of the manifold gas heating plate150D from the inlet 180. The manifold gas heating plate 150D illustratesthat the channel(s) 195 may be provided in any configuration to allowtime for reaction precursors to absorb heat from the manifold gasheating plate 150 and allow the temperature thereof to rise to anelevated temperature.

FIG. 2E shows a manifold gas heating plate 150E with a spiral channel195-e that has circumferential passes thereof formed in a peripheralportion of the manifold gas heating plate 150E but not in a centralportion thereof. A loop of the channel 195-e proceeds from the last passof the spiral around the manifold gas heating plate 150E, locatedpartway from the center to the periphery of the manifold gas heatingplate 150E, to the center of the manifold gas heating plate 150E. Such aconfiguration may be used if the residence time of reaction precursorsachievable by using a full spiral is not needed. The outlets 190 inmanifold gas heating plate 150E are also arranged along a diameter thatdoes not include the inlet 180, but in this case is perpendicular to adiameter that includes the inlet 180.

FIG. 2F shows a manifold gas heating plate 150F with a spiraloid channel195-f that includes branches 182. The channel 195-f proceeds from theinlet 180 to a first branch point 182 where the channel 195-f dividesinto two branches. Each branch continues along a spiraloid path throughthe manifold gas heating plate 150F to a second branch point 182, onefor each branch. Each second branch point divides the branch into twosub-branches, for a total of four sub-branches. Each sub-branch ends atan outlet 190. The manifold gas heating plate 150F illustrates howbranched channels may be implemented in a manifold gas heating plate150. It should be noted that channels and branches may also converge ina manifold gas heating plate 150 at one or more convergence points.

FIG. 3A is an exploded perspective view of the manifold gas heatingplate 150, the gas injector 170 and the manifold support 196 showing thepositions each member has when installed in the chamber 100. Uponinstallation, the gas injector 170 is inserted into the opening 169(FIG. 1A), and the manifold support 196 is inserted into the recessopposite the opening 169 (FIG. 1A) from the inside the chamberprocessing volume 120. The manifold gas heating plate 150 is thendisposed on the gas injector 170 and the manifold support 196 so thatthe inlet 180 fits over the extending conduit 185. The junction of theextending conduit 185 and the inlet 180 may be sealed using a thermallyresistant seal member disposed between the extending conduit 185 and theinner wall of the inlet 180. In the event a two-injector embodiment isused, a second gas injector 170 may be inserted into a second openinglike the opening 169 that would be located where the recess is shown inFIG. 1A, and both openings 169 would fit over a respective gas injector.Each injector may be sealed to the manifold as described above. Othersealing and connection mechanisms, such as snap rings, o-rings, threads,and plugs, can be used under appropriate conditions to minimize oreliminate leakage of gas at the coupling between the extending conduit185 and the inlet 180. Alternatively, the extending conduit 185 may justalign with the inlet 180 without forming a seal so that a stream of gasflows out of the extending conduit 185 toward the inlet 180, crosses agap between the extending conduit 185 and the inlet 180, andsubstantially flows into the inlet 180.

FIG. 3B is an isometric view of a gas injector 170 according to oneembodiment. The gas injector 170 has two flat sides 171 connected byrounded side walls 172 and a gas inlet 175 at a first end 173 of the gasinjector 170. The gas inlet 175 is an opening that defines a planesubstantially perpendicular to a central axis of the gas injector 170,the central axis defining a gas flow direction through the gas injector170. A second end 174 of the gas injector 170, opposite from the firstend 173, is closed off. The extending conduit 185 is located near thesecond end 174 of the gas injector 170, between the first end 173 andthe second end 174 thereof, to provide connection or engagement with theinlet 180 of the manifold gas heating plate 150. The second end 174 mayhave a concave rounded shape consistent with the circular shape of theprocessing volume 120 and the substrate support 140 (FIG. 1A). Othershapes of gas injectors 170 are envisioned. For example, the gasinjector 170 may be a tube that runs through a circular opening of theside wall of the chamber body 102 and into the inlet 180 of themanifold. In another example, the gas injector 170 may have an elongatedinlet like the gas inlet 175 at the first end 173 as shown in FIG. 3B,and may narrow at the second end 174 to a tube that turns to connectwith or engage with the inlet 180 of the manifold gas heating plate 150.

FIG. 3C is an exploded perspective view of a manifold 350, a gasinjector 370 and a manifold support 196. The gas injector 370 isdifferent from the gas injector 170 in that the gas injector 370 hasthree extending conduits 185-a through 185-c that each engage with arespective inlet 180A-C of the manifold 350. Each of the three extendingconduits 185 is located between the first end 173 and the second end 174of the gas injector 370. Each inlet 180A-C fluidly couples to arespective one of the spiral channels 395-a through 395-c connected tooutlets 190. The assembly of FIG. 3C provides three separate channels,and thus three separate gas pathways, in the manifold 350 to segregatethree gases for heating thereof before they enter the processing volume120.

FIG. 3D is an isometric view of the gas injector 370 of FIG. 3C. The gasinlet 175 of the gas injector 370 is divided into a plurality ofseparate gas lines 155-a to 155-c. In this case, the gas inlet 175 hasthree separate gas lines 155-a through 155-c, each fluidly coupling witha different one of the three ports 185-a through 185-c. The ports 185-athrough 185-c are staggered to allow engagement with both the gas lines155-a through 155-c and the inlets 180A-C, which extend in directionsthat are at right angles to each other. Separate gas pathways coupled tothe separate gas lines 155-a through 155-c allow a plurality of separategases, or separate gas mixtures, to flow into the gas inlet 175, andthrough the manifold 350, separately, if desired. A flow regulator 157may be provided in one or more of the gas lines 155-a through 155-c toallow flow rate control of reaction precursors into the chamber. Asillustrated in FIG. 3D, the gas line 155-b has a flow regulator 157.

FIG. 4A is a perspective cross-sectional view of a chamber 400 accordingto another embodiment. The chamber 400 is similar to the chamber 100 inmany respects, and identical features in the two chambers are labelledidentically. The chamber 400 is different from the chamber 100 in howgas flows from the gas injector 170 to the processing volume 120.Instead of a manifold gas heating plate 150, a blocker plate 450 is usedas the gas heating plate, and gas flows between the blocker plate 450and the divider 165 to be heated by the blocker plate 450 and thedivider 165. The blocker plate 450 has a first major surface 466 and asecond major surface 467, with the second major surface 467 facing thesubstrate support when the blocker plate 450 is installed in the chamber400.

The blocker plate 450 has an opening 480 that extends through theblocker plate 450 from the first major surface 466 to the second majorsurface 467 thereof allowing gas to flow from the extending conduit 185,through the blocker plate 450, and to a plenum 410 between the blockerplate 450 and the divider 165. The blocker plate 450 includes aplurality of baffles 420 extending from the blocker plate 450 toward thedivider 165 to create flow pathways through the plenum 410. Gas flowsthrough the opening 480 into the plenum 410 along the pathways formed bythe baffles 420 to absorb heat from the blocker plate 450 and thedivider 165. A plurality of ports 490 is formed in the blocker plate 450to allow gas to flow from the plenum 410 to the processing volume 120.

The blocker plate embodiment of FIG. 4A is similar in concept to themanifold embodiment of FIG. 1A in that a gas flows along a pathway thatsubjects the gas to heating before the gas enters the processing volume.In both embodiments, the gas is heated by contact with hot surfaces ofthe pathway, which are heated in turn by the heat source 160. Injectionof the second gas through the second opening 126 is the same, and gasexhaust from the chamber 400 is the same, as the chamber 100. Theblocker plate 450 may also be made of materials substantiallytransparent to the electromagnetic radiation emitted by the heat source160. The blocker plate 450 may also have coatings on the first andsecond major surfaces thereof 466 and 467, as described above for themanifold gas heating plate 150.

The blocker plate 450 of FIG. 4A and the divider 165 may form a singlebody. The blocker plate 450 may be formed with baffles, and then thedivider 165 may be permanently attached to the baffles, for exampleusing adhesive or by welding. Alternatively, grooves may be formed inthe divider 165 to receive the baffles 420 of the blocker plate 450 toprovide sealing of the gas flow pathway in the plenum 410.

FIG. 4B is a top view of the blocker plate 450, showing the openings 180and 190 and the baffle 420. In FIG. 4B, one spiral baffle 420 is shown.The blocker plate 450 has a rim 455, which is raised like the baffle 420and contacts the divider 165, as shown in FIG. 4A. The rim 455 providessealing at the edge of the blocker plate 450 so gas flowing through theopening 180 is forced to flow through the plenum 410, through theopenings 490, and into the processing volume 120. The divider 165 mayalso have a groove to receive the rim 455. As with the variousembodiments of the manifold gas heating plate 150, the blocker plate 450may have various configurations of baffles and openings to provide anydesired flow pattern through the plenum 410 between the blocker plate450 and the divider 165.

The blocker plate 450 differs from the manifold gas heating plate 150chiefly in that the surface of the blocker plate 450 that faces thedivider 165 when installed has a number of features, where the samesurface of the manifold gas heating plate 150 is flat. The blocker plate450 has openings that extend from the first major surface 166 to thesecond major surface 167 through the thickness of the blocker plate 450,whereas the manifold gas heating plate 150 has openings only on oneside, the side facing the substrate support 140 when installed. Theblocker plate 450 also has baffles on the side facing the divider 165,which here is the first major surface 466, where the manifold gasheating plate 150 has no such baffles. The blocker plate 450 and themanifold plate 150 are both embodiments of a plate that defines gas flowconduits, the channels 195 of the manifold gas heating plate 150 and theplenum 410 of the blocker plate between the baffles 420. The gas flowconduits of both types form a heating space for gas flowing to theprocessing volume 120.

The outlets 190 described in connection with the various embodiments ofthe manifolds 150, and the openings 490 described in connection with theblocker plate 450, may be shaped to direct gas flow in a desireddirection into the processing volume 120. FIG. 4C shows a detailed viewof a blocker plate 451, like the blocker plate 450, with an opening 491that is angled to direct gas flow in a desired direction. Like theopening 490, the opening 491 extends through the blocker plate 451 fromthe first major surface 466 to the second major surface 467, fluidlycoupling the plenum 410 to the processing volume 120. The opening 491has an axis 492 that is not perpendicular to either the first majorsurface 466 or the second major surface 467.

Angling the outlets 191 and openings 491 with respect to the first andsecond major surfaces 166, 167 or 466, 467 allows directing gas flow ina selected direction or to a desired radial location on the substrate104. The outlets 190, 191, and openings 490, 491 may also have a shapedflow pathway to influence divergence of the gas upon exiting the outlets190, 191 and openings 490, 491. For example, the outlets 190, 191 andopenings 490, 491 may have a diameter that increases toward an exitpoint of the outlet 190, 191 or opening 490, 491 to promote spreading ofthe gas entering the processing volume 120. In other aspects, theoutlets 190, 191 and openings 490, 491 may have shapes that are notcircular. For example, some or all the outlets 190, 191 and openings490, 491 could be elongated in a direction along the second majorsurface 167 in the case of the outlets 190, 191, and along the firstand/or second major surfaces 466, 467 in the case of the outlets 490,491.

While resident in the manifold gas heating plate 150, and/or between theblocker plate 450 and the divider 165, reaction precursors are heated bythe manifold gas heating plate 150, or blocker plate 450 surfaces heatedby the heating source 160. Increasing the length of the channel 195 willincrease in residence time of the reaction precursors at a given flowrate. An increased residence time of the reaction precursors in themanifold gas heating plate 150 or the blocker plate 450 will, therefore,correlate with an increased temperature of the gas prior to it flowinginto the processing volume 120. For example, in some embodiments thelength of the channel(s) 195, or the flow path through the plenum 410,and power of heating source 160 are selected to provide heating of thereaction precursor to above 400° C., which can activate hydrogen gas fora semiconductor oxidation process that uses hydrogen gas and oxygen gasto form reactive species that react with the substrate surface.Residence time can also be influenced by flow rate through thechannel(s) 195 or the plenum 410. The reaction precursor to be heatedcan be diluted using a carrier gas to adjust the flow rate (Q) thereofthrough the channel(s) 195 or the plenum 410 to achieve a desiredresidence time for heating of the precursor gas independent of the flowrate through the channel(s) 195 or the plenum 410. The manifold gasheating plate 150 may have a convex or concave curvature on one or bothsides thereof in some cases. The blocker plate 450 may likewise have asimilar convex or concave curvature, and the divider 165 may be curvedto match, or the baffles may have dimensions that provide a flat contactplane for engaging with the divider 165.

FIG. 5 is a schematic top view of a processing chamber 500 according toanother embodiment. The processing chamber 500 is like the processingchambers 100 and 400, but the processing chamber 500 accomplishesheating of a precursor gas in another way. The processing chamber 500has a first gas inlet 502 at a first location through a side wall 504 ofthe chamber 500 and a second gas inlet 506 at a second location throughthe side wall 504. The second location is azimuthally spaced at an angleof about 90° from the first location. A substrate access door 510 isopposite the second gas inlet 506, and an exhaust (not shown) is locatedwithin the chamber body adjacent to the substrate access door 510.Instead of the gas injectors and plates of the chambers 100 and 400, agas heater 508 is coupled to the first gas inlet 502 to heat the gasflowing to the first gas inlet 502. The gas heater 508 directly heats agas flowing into the first gas inlet 502 of the chamber 500. The gasheater 508 may be a resistive heater or a heat exchanger having a highsurface area for contacting the gas flowing through the gas heater 508.

While the foregoing is directed to embodiments of the present invention,other and further embodiments of the invention may be devised withoutdeparting from the basic scope thereof, and the scope thereof isdetermined by the claims that follow.

What is claimed is:
 1. A processing chamber comprising: a gas injectionapparatus comprising: a gas injector having an inlet at a first end, aclosed second end, and an extending conduit located between the firstend and the second end; and a transparent gas heating plate having afirst major surface and a second major surface opposite the first majorsurface, a first opening that matches and fluidly couples to theextending conduit and a second opening, the gas heating plate definingat least one circuitous gas flow path from the first opening to thesecond opening; and a radiant heat source facing the gas heating plate.2. The processing chamber of claim 8, wherein the gas heating plate is amanifold plate gas heater, the at least one circuitous gas flow path isa channel formed in the manifold plate gas heater, the first opening isan inlet to the channel, and the second opening is an outlet from thechannel.
 3. The processing chamber of claim 9, wherein the gas injectorhas a plurality of ports, the manifold plate gas heater has a pluralityof inlets, each matching one of the plurality of ports, and the gasinjector has a plurality of gas lines, each fluidly coupled to one ofthe plurality of ports.
 4. The processing chamber of claim 10, whereinat least one of the gas lines has a flow regulator.
 5. The processingchamber of claim 10, wherein the manifold plate gas heater has aplurality of channels running between the first major surface and thesecond major surface.
 6. The processing chamber of claim 9, wherein thechannel is branched.
 7. The processing chamber of claim 8, wherein thesecond opening has an axis that is not perpendicular to either the firstmajor surface or the second major surface.
 8. The processing chamber ofclaim 8, further comprising a divider between the gas heating plate andthe heat source, wherein the gas heating plate is a blocker plate havingbaffles that, together with the divider, forms a plenum containing theat least one circuitous flow path.
 9. The processing chamber of claim15, wherein the gas heating plate is attached to the divider.
 10. Theprocessing chamber of claim 15, wherein the at least one circuitous flowpath is branched.
 11. The processing chamber of claim 8, wherein the gasheating plate and the gas injector are made of quartz.
 12. Theprocessing chamber of claim 8, wherein the gas heating plate is curved.13. A processing chamber, comprising: a chamber body having a side wallwith a first gas inlet, a second gas inlet, and an exhaust opposite thesecond gas inlet; a substrate support disposed in the chamber body anddefining a substrate processing plane proximate to the first and secondgas inlets and the exhaust; a radiant heat source facing the substratesupport; a divider between the heat source and the substrate support;and a resistive gas heater coupled to the first gas inlet.